大口径光电探测设备主镜晃动的误差补偿

Error compensation for primary mirror shaking of large aperture optical detection equipment

针对大口径光电探测设备在随俯仰角变化时由于主镜支撑点的变化而产生的晃动,研究了在静态测量时如何补偿主镜晃动造成的误差以提高大口径望远镜的静态测量精度。首先给出了一个1m口径望远镜的支撑结构和力学模型,在分析了传统三轴误差补偿方法和球谐误差补偿方法的基础上提出了针对大口径望远镜的误差补偿方法。在外场对光测设备进行了标校实验,选取32颗恒星在修正了蒙气差后对各个系统差进行求解,得出了主镜晃动误差和三轴差。与传统误差补偿方法的比较结果显示:加入主镜晃动误差补偿后,望远镜的静态测量精度从15.4″提高到了2.5″。此种方法物理意义明确,各误差分量重复性好,对主镜晃动误差进行补偿修正后提高了大口径望远镜的静态测量精度。

Large aperture optical detection equipment has the shaky with its elevation angle changing when the support point of primary mirror changes. This paper studies how to compensate the measuring errors caused by the primary mirror shaking and to improve the static measuring accuracy of the large aperture optical detection equipment. Firstly, the supporting structure and mechanic model of a lm diameter telescope were presented. Then, a new error compensation method for the large aperture telescope was proposed based on the analysis of the traditional three axis error compensation method and spherical harmonic error compensation method. The calibration experiments for the optical detec- tion equipment was performed. By selecting 32 stars whose refractions had been revised, the error of each system was solved to obtain the primary mirror shaking error and the three axis difference. As comparison with the traditional error compensation method, it shows that the static measurement accuracy of the telescope has increased from 15.4 ＂to 2.5 after the shaking error of the primary mirror is compensated. It concludes that the physical meaning of this method is clear, and each error component has good repeatability. It improves the static precision of large aperture telescope by compensating the shaking errors of primary mirror.